Building structural system

ABSTRACT

Structural units comprising laminated, skin-stressed, panels and attendant components are joined in various combinations by connecting members so as to form frameless, load-carrying structures affording a clear span desirable not only in commercial, industrial and institutional applications but in residential construction as well. The structural system especially lends itself to factory manufacture and assembly in maximum size transportable sections completely finished for jobsite installation on pre-arranged foundations. The term panel is used herein in its broadest sense and denotes a structural member substantially greater in the dimensions of length and width than in thickness. The term structural unit is more comprehensive than the term panel and includes not only a panel but also various components associated with a panel.

United States Patent Greenamyer BUILDING STRUCTURAL SYSTEM Filed:

Assignee: Building Structural Systems, Inc.,

Carson City, Nev.

Jan. 24, 1972 Appl. No.: 220,316

US. Cl 52/463, 52/467, 52/584,

Int. Cl E04b 1/41, E04b 7/02 Field of Search... 52/90, 93, 73, 309, 584,405,

References Cited UNITED STATES PATENTS Douglas, Jr. 52/584 X Dreisel52/584 X Stack 52/580 X Stephens 52/406 X McCown 52/405 X Hipple 52/93 XSohns 52/309 Weinroft 52/615 X Schrofer et a1. 52/309 X Potter Feb. 26,1974 FOREIGN PATENTS OR APPLICATIONS 1,262,049 4/1961 France ..52/615370,222 6/1963 Switzerland ..52/404 Primary ExaminerAlfred C. PerhamAttorney, Agent, or Firm-Lothrop & West [5 7] ABSTRACT Structural unitscomprising laminated, skin-stressed, panels and attendant components arejoined in various combinations by connecting members so as to formframeless, load-carrying structures affording a clear span desirable notonly in commercial, industrial and institutional applications but inresidential construction as well. The structural system especially lendsitself to factory manufacture and assembly in maximum size transportablesections completely finished for jobsite installation on pre-arrangedfoundations.

12 Claims, 19 Drawing Figures PATENTEDFEBZB 1974 3793389 sum 2 ur 7 Fiii |----i hashes PATENTEUFB26 1974 SHEET 5 OF 7 ,1 BUILDING STRUCTURALSYSTEM I The invention relates to improvements in systems forconstructing buildings in which structural units including panels andappropriate additives and connectors serve as floor, bearing walls,roofs and partitions.

The prior art affords numerous disclosures of structures fabricated fromstructural units serving multiple purposes, but none, so far as isknown, provides a combination of structural units and connectors whichcan be so joined as to fulfill substantially any kind of structuraldesign requirement.

It is therefore an object of the invention to provide a buildingstructural system which is versatile in that it is capable of being usedto advantage in constructing buildings of a myriad of different kinds,sizes and styles.

It is another object of the invention to provide a building structuralsystem in which labor at the jobsite is reduced'to a minimum owing tothe accuracy and degree of completion obtainable at the factory, wherebetter quality control and efficiency can be exercised.

It is still another object of the invention to provide a buildingconstruction system which is economical, not only with respect toinitial construction costs but also in connection with repair andmaintenance expense.

It is yet another object of the invention to provide a buildingconstruction system which provides long span carrying capacities withfewer under-floor supports and internal columns or bearing walls.

It is a further object of the invention to provide a building structuralsystem which. is not only light in weight, structurally stable and easyto erect, but which is also substantially impervious to fungus, bacteriaor insects, and affords a high degree of thermal insulation andsoundproofing.

It is a still further object of the invention to provide a buildingstructural system which is highly resistant to the elements, to attackby fire and to seismic action.

It is yet a further object of the invention to provide a buildingstructural system in which not only electrical services and accessories,but also plumbing, heating and air-conditioning systems are easilyinstalled and well protected.

It is another object of the invention to provide a building structuralsystem which readily lends itself to use with all types of interior andexterior wall and ceiling finishes as well as all kinds of roof andfloor coverings of a decorative and protective nature.

It is an additional object to provide a generally improved buildingstructural system.

Other objects, together with the foregoing, are attained in theembodiments described in the following description and shown in theaccompanying drawings, in which:

FIG. 1 is a fragmentary exploded isometric view of a stylized structuregenerally illustrating how the structural units and connecting membersare combined to form a one-room building, the end wall units not beingshown so as to clarify the disclosure;

FIG. 2 is a fragmentary, exploded, sectional view to a greatly enlargedscale, showing a typical flushproject type of connector means, the planeof the section being indicated by the line 22 in FIG. 1;

FIG. 3 is a side elevational view of the FIG. 1 structure in assembledposition, illustrating in stylized manner one type of foundationutilized in the present system;

FIG. 4 is a transverse sectional view of the FIG. 1 structure inassembled position the plane of the section being indicated by the line4-4 in FIG. 3;

FIG. 5 is a fragmentary vertical sectional view, to an enlarged scale,showing a typical floor to wall connection, the plane of the sectionbeing indicated by the line 5-5 in FIG. 6;

FIG. 6 is a view comparable to FIG. 5, showing a typical floor to wallconnection, taken on the horizontal plane 6-6 in FIG. 5

FIG. 7 is a fragmentary horizontal sectional view to an enlarged scaleshowing atypical wall to wall comer connection;

FIG. 8 is a fragmentary, exploded, sectional view, to an enlarged scale,showing a typical project-project type of connector means;

FIG. 9 is a fragmentary, exploded, sectional view, to an enlarged scale,showing a, typical flush-flush type of connector means, the plane of thesection being indicated by the line 9-9 in FIG. 1;

FIG. 10 is a view comparable to FIG. 9, but showing a modified form offlush-flush type of connector;

FIG. 1 1 is a view comparable to FIG. 9, but showing a modified form ofproject-project type of connector;

FIG. 12 is a view comparable to FIG. 1 1, but illustrating a fiirthervariation of a project-project" type of connector;

FIG. 13 is a view comparable to FIG. 2, but showing a modified form of aflush-project type of connector;

FIG. 14 is a view comparable to FIG. 2, but in inverted attitude andshowing a form of project-flush" connector with closure'cap to excludethe elements, the plane of the section being indicated by the line 14-14in FIG. 1;

FIG. 15 is a transverse sectional view of a simplified buildingstructure having a shed type of roof and a cantilevered deck, thesection being taken through two of the concrete piers supporting thestructure;

FIG. 16 is a fragmentary sectional view, to a greatly enlarged scale, ofone of the concrete pier and pipe supports shown in FIG. 15;

' FIG. 17 is a view comparable to FIG. 16 but taken at right anglesthereto; 7

FIG. 18 is a fragmentary sectional view to an enlarged scale of atypical wall to roof, or haunch, connection; and, I

FIG. 19 is a graph showing strength characteristics of various types ofconnectors, showing the uniform load necessary to deflect a connectedpair of structural units a predetermined amount-for different spans.

While the building structural system of the invention is susceptible ofnumerous physical embodiments, depending upon the environment andrequirements of use, substantial numbers of the herein shown anddescribed embodiments have been made, tested and used, and all haveperformed in an eminently satisfactory manner.

The structural system of the invention, generally designated by thereference numeral 12, can be used in the construction of buildings ofall types, including residential, commercial and institutional, as wellas in the field of mobile structures.

In the simplified and somewhat stylized form of building structure shownin FIGS. 1, 3 and 4, only a floor, two side walls and a gable type ofroof are illustrated. In the interests of clarifying the disclosure, theend walls are now shown. Each of the structural units, collectivelydesignated by the reference numeral 13, is preferably of modularconfiguration, with a module base of four feet. Thus, for example, inFIG. 1, 3 and 4, each of the six roof units 14 is four feet wide andtwelve feet long; each of the wall units 15 is four feet wide and eightfeet high; and each of the floor units 16 is four feet wide and feetlong.

Either at the factory or on the jobsite, openings in the structuralpanel units can readily be made, as by sawing. Thus, a door opening 17to receive a door 18, and a window opening 19 to receive a window 21,can quickly be formed either by a band saw or circular saw cuttingthrough the unit.

Construction of the panel 20 itself is of the laminated type comprisinga planar slab-like core 22 (see FIG. 2) of foamed material having verylow thermal conductivity. To each side of the core, a metal skin 23 and24, or sheath, is bonded, the metal sheath being preferably of aluminumor light gauge steel. The overall thermal conductivity (u) of a typicalpanel is in the approximate range of 0.03 to 0.07.

The panel core 22 can either be in the form of a precast block of rigidfoamed material, such as polystyrene, to which the metal skins arebonded by an appropriate adhesive, or the core can be foamed in place byintroducing and combining the necessary ingredients between the parallelmetal boundary skins spaced apart the required distance by suitablemeans. Polyurethane, for example, has been utilized with veryconsiderable effectiveness as a core material, a strong bonding betweenthe core and the metal skins occurring as the core expands intoengagement with the inner surfaces of the metal skins and exerts astress thereon. The prestress, in fact, greatly increases beam andcolumnar strength. Where appropriate, increased fire resistance isafforded by using foamed vermiculite, perlite, asbestos, or the like, inthe core.

As most clearly appears in FIGS. l, 3 and 4, each of the three floorunits 16 (each being, for example, 4 ft. wide and 20 ft. long) includesa pair of opposite end edges 26 and a pair of opposite side edges 27,collectively termed marginal edges; and a building of any desired lengthcan be made merely by adding more units.

So also, as will be appreciated, coverting the FIG. 1 structure into abuilding of any desired width is readily accomplished by multiplying thespan by the use of multiple rows of interior columns in conventionalmanner.

With particular reference to FIGS. 1 and 3, it can be seen that in orderto form a strong, rigid unitary floor, it is only necessary to jointogether the longitudinal side edges 27 of the central one of the floorunits 16 to the adjacent abutting longitudinal side edges 27 of the twostraddling units 16.

The joint must be such as to fulfill the structural design requirementswith respect to span and load, and to establish and maintain thedimensions required in a system of building construction using factorymade components for the most part.

Meeting all such requirements in an entirely satisfactory manner is theconnector 31 shown in FIG. 2 wherein the two adjacent side edges 27 ofthe floor 4 units 16, for example, are to be joined. The connector 31 issymmetrical about a central vertical plane 32 and includes on each sideof the central plane 32 a sturdy, elongated strap 33, or plate, or web,or metal, preferably extending the entire unit length (20 ft. in thecase of the floor unit 16 shown in FIG. 1). Each of the webs 33 issecured by fasteners 34, at appropriate intervals,

(or bonded with pressed contact cement, such as adhesive 370, a productof Pittsburgh Plate Glass Co.) to an adjacent beam 36 which can be ofwood. As will be seen, the beam 36 serves not only as a spacer and websupport but also as a structural additive in substantially increasingthe strength and rigidity of the floor.

Interposed between the beam 36 and the adjacent side edge of the panelcore 22 is a cushion 41, or pad, or sea], of resilient material, such asfoamed elastomeric material or flexible foamed plastic," which affords abuffer zone and barrier between the beam 36 and the adjacent side edgeof the core 22. Flexible polyurethane has beenused to good advantage ascushion material.

The upper metal skin 23 extends over the top of the seal 41 and the beam36 to form a projection 43 which also overlies the upper end portion ofthe adjacent one of the webs 33 and thereby abuts the adjacent skinprojection 43 when the connector is installed. Thus, after the twoadjacent floor units 16 are firmly abutted (with the webs 33 havingpreviously been fastened to the adjacent beams 36) so that the two websare in close, face to face engagement, the upper ends of the twoabutting units are clamped together by a plurality of strong staples 44driven downwardly by a power-driven staple gun through the metal skinprojections 43 and into the subjacent beam edges. The staples 44 arespaced a few inches apart along the entire length of the floor unitoint.

At the same time, the lower ends of the web plates 33, the beams 36 andthe downturned flanges 47 of the two lower metal skins 24 are securedtogether by a plurality of through bolts 48 and power driven nuts 49, orcomparable fasteners.

In the form of connecting member 31 illustrated in FIG. 2, both the webplates 33 and the beams 36 extend downwardly beyond the horizontal planeof the bottom surface of the two units whereas the top surface of thejoined units is flush, as is of course desirable for a floor surface.For this reason, the FIG. 2 form of connector, indicated by thereference numeral 31, is of the kind termed herein as a flush-projecttype of connector wherein one side is flush, and the other sideprotrudes.

As will subsequently be disclosed, other classes of connectors are ofthe flush-flush type and still others are of the project-projectvariety; and within each of these classes further modifications exist toaccommodate varying requirements of design and cost.

Prior to laying the floor, a foundation 5] will have been installed. Inthe elementary form of structure shown in FIGS. 3 and 4, the foundationcan be of a suitable concrete construction, for example, a plurality ofpiers 52, 53, 54 and 55 on opposite sides of the structure. The piersare located so as to support the corners of all of the three structuralunits 16 forming the floor.

After the floor is installed with the units spanning the piers 52 55 onopposite sides of the building, and the connectors 31 are firmlysecured, the walls of the build- 7 structure, as appears in FIGS. 1, 3and 4, and joined together by connectorsof the appropriate type. Atypical wall to floor connection is disclosed in FIGS. 5 and 6.

Should it be desired that the inside surface of the wall be flush andthe outside surface be interrupted at intervals, so as to provide anexterior board and batten-like effect, the flush-project form ofconnector shown in FIG. 2, and previously described in detail, would be.very appropriate and is therefore shown herein.

Thus, as appears in FIGS. 1, 5 and 6, the joint between the middle oneof the three wall units and the right hand one of the wall units 15 onboth sides of the building) is provided with a connector 31 of theflushproject type, as is shown in detail in exploded form in FIG. 2 andin assembled form in FIGS. 5 and 6.

FIGS. 5 and 6 are vertical and horizontal sectional views, respectively,of a typical floor to wall connection and illustrate, for example, aFIG. 2 form of connector 31 in assembled condition, with the same typeof connector 31 for both the horizontal floor and the vertical walls.

In FIGS. 5 and 6, the upper skin 23 of the floor unit 16 comprises theupper surface of the building floor and, as can be seen, the twohorizontal adjacent floor units 16 are joined by the connector 31including the two metal webs 33 and the two beams 36. The webs and beamsare each joined together by fasteners 34 and both are joined byfasteners 48 and 49 to the downturned flanges 47 of the floor units 16.The horizontal beams 36 and webs 33 forming a girder 60 are supported onthe foundation '51 and, if desired, an elongated U-shaped protector cap56 can be placed over the bottom and sides of the girder 60 and securedby fasteners 57 as shown in FIG. 5.

Preferably, the floor to wall construction includes not only thecustomary sealing strips 41 between the cores 22 and adjacent beams 36along the lateral side edges of the units, but also a sealing stripalong the lower end edges of the units. The sealing strip 58 is laidhorizontally on top of the floor 16 around the room perimeter, at thefoot of the vertical wall units 15, and is slightly less in transversewidth than the thickness of the verticalv wall unit 15, the thickness ofthe wall unit 15 being, in the present instance, about four inches. Thehorizontal sealing strips 58 are preferably of flexible polyurethanematerial, which is spongy in nature and is compressed, by the weight ofthe superposed vertical wall unit 15 from an uncompressed thickness ofvabout onehalf inch to a compressed thickness of approximately one-fourthof an inch or less.

Above the horizontal sealing strips 58 are horizontal retainer strips59. of wood, such as plywood, fiveeighths inch thick and 3 7/8 inchwide, each strip extending between the vertical posts 45, or studs,formed,-

as before, of face to face'metal webs 33 fastened to beams 36 andsealing strips 41 interposed between the beams 36 and the adjacentexposed edges of the solid foam'core 22.

Fastenings 50, such as screws, secure the horizontal plywood retainerstrips 59 and the seals 58 to the subjacent skin 23 and rigid foam core22. After the retainer strips are fastened down, the vertical wall units15 are placed in position, the skins 23 and 24 on the lower ends of thewall units 15 being extended to form aprons covering the side edges ofthe horizontal sealing strips 58 and retainer strips 59. As before,suitable fasteners, including staples 44, are utilized to afford astrong, rigid connection.

Depending upon design requirements, variant formsof connectors are used.One of the variant forms is a project-project type of connector 61 asappears most clearly in FIG. 8. Thefull project-project connector 61includes, as before, a facing pair of web plates 62 interposed between apair of spacer beams 63 separated from the respective pair of cores 22by a pair of resilient sealing cushions 64, or pads, extending the fulllength of the structural units. When all parts are abutted in snugrelation, fasteners, such as staples 66 and bolts 67 and nuts 68, can beused to connect the units in a strong and rigid manner, registeringthrough bores having been pre-drilled at the factory in the usual case.

FIG. 9 illustrates still another form of connector. This connector is ofthe flush-flush type and is designated by the reference numeral 71. Hereagain, the connector member 71 is characterized by a facing pair ofelongated metal webs 72, or straps, preferably extending the entirelength of the structural units. Next to the webs 72 is a pair of beams73, and interposed between the beams 73 and the respective cores 22 is aresilient strip of cushioning material forming a buffer pad 74. Thecoplanar ends of the metal skins 23 project over the respective ends ofthe pad 74, the beam 73 and the web 72, so that the adjacent edges ofthe skins 23 abut when the connector is installed in final position andsecured as by stapling with a plurality of power driven staples 76. Thesame construction prevails on the opposite side of the panel where thepanel skins 24 abut and the connector 71 is secured by staples 77. Theconnector 71, in other words, affords a smooth, continuous surface onboth sides of the wall and lends itself especially well, for example, tothe installation of decorative interior plywood paneling or to theapplication of other decorative and protective exterior'or interiorcoatings, such as paint, stucco or plaster.

A modified form of the flush-flush type of connector appears in FIG. 10and is designated by the reference numeral 79. A pair of C-shapedchannels back up to a central plate 81 and are spot welded thereto toform an I-beam 82 extending the full length of the panel. Theoverhanging extensions of the skin 23 and 24 are welded to the subjacentflanges of the I-beam 82. This form of connector does not necessarilyutilize wooden beams as fillers and stifi'eners- It does use, how ever,a seal 83 on both exposed edges of the foamed core 22 and can include anappropriate filler member, if desired.

Still other exemplary types-of connectors which do not employ woodenbeams are illustrated in FIGS. 11 to 14.

FIG. 11- shows an elementary project-project type of connector 85comprising an opposed pair of web plates 86 secured to the flanges 87and 88, respectively, of the metal skins 23 and 24, as by fastenings 89and 90, or by riveting or welding. Flexible polyurethane pads 91 areinterposed, as shown. This type of connection is of especial utilitywhere insect proofness takes precedence over dimensional accuracy.

The connector 92 shown in FIG. 12 illustrates the manner in which theproject-project" FIG. 11 form of device can be strengthened, as bydoubling the number of web plates 86 and by also interposing a pluralityof stiffening plates 93 therebetween. Welding affords a reliable methodof joining all components, including the plates 86, the plates 93 andthe respective upper skin flanges 87'and lower skin flanges 88, into anextremely rigid structural member, although recognizing thatconventional, power-driven fasteners or rivets can also be utilized togood effect.

FIG. 13 discloses a modified 11 flush-project or project one-side typeof structure 95 wherein the adjacent flange ends 96 of the metal skins23 are bent inwardly to lie between the web plates 97 and the flexiblepads 98. The bottom flanges 99, however, are outwardly directed tooverlie the downwardly projecting portions of the web plates 97.Appropriate securing means, such as welding, bolting, riveting or thelike, can be used to effect a firm, rigid connection.

As will be recognized, still other variations of the foregoingarrangements can be used to fulfill differing design requirements.

FIG. 14, in fact, discloses a variant form of projectflush or projectone-side connector somewhat comparable to the connector 31 in FIG. 2 butinverted so that the projecting'portion extends upwardly, such as on theroof of the building shown in FIG. 1, and the flush portion is on theceiling and faces downwardly. To preclude the entry of rain, snow andthe like, an elongated protective cap 65, or inverted U-shape in sectionsheet metal, is mounted over the upwardly projecting beams, beingsecured by washered nails 70. It will be recognized that cap members canbe used wherever desired, for example, as indicated by the numeral 65inFIG, 6 where the cap 65 covers the exterior projecting portion of thevertical wall stud 45. Fasteners, such as through bolts 75 and staples44, clamp the components together.

FIG. 7 illustrates a common form of connector used at corners to jointwo vertical units at an angle, such as the customary 90 corner angle.Covering the usual sealing strips 41 on the exposed ends of the rigidfoamed cores 22 of the units 15 are metal plates 100 and 101, ofaluminum or steel strip stock (approximately 3 178 inch wide with 26gauge thickness for steel and 0.032 inch thickness for aluminum). Bothof the extended flange ends 102 of one of the wall units 15 are bentinwardly to embrace theenclosed plate 101; and the extended flange ends103 and 104 of the other abutting unit are arranged, as shown in FIG. 7,to overlie one of the flanges 102 and the adjacent panel skin 23,respectively. A. strong, rigid comer construction results when theforegoing components are fastened together as by spot-welding or screwfastenings at the locations 105, 106, and 107.

FIGS. 15 through 17 illustrate how a pier-supported structure 109 havinga shed type roof 111, for example, with extensive overhang ll2 above acantilevered deck 113 can be built using the structural unit andconnector system of the present invention. In the structure 109, theroof units are identified by the reference numeral 114, the floor unitsby 116 and the wall units by 115.

Anchored in concrete piers 110 in auger holes in the ground 117 arevertical pipes 118 supporting girders 1 l9 fastened by screws 120 toplates 121 welded to the top of the pipes 118. Angle irons 122, fastenedby screws 123 to the girders 1 19, project upwardly and are theresecured by fasteners-124 to floor joists oriented at right angles to andsupported by the girders. The floor joists serve to connect adjacentfloor units 116 and comprise, as before, a pair of beams 126 with aninterposed pair of metal web plates 127 and seals 128 between the cores22 and beams 126. The beams 126 and the plates 127 are clamped togetherby bolts 129. Downturned flanges 147 of the floor units 116 are securedto the beams 126 by fasteners 150.

It is particularly to be noted that the extraordinary beam strength ofthe stressed skin and adhesivelybonded, rigid-core construction of thestructural units permits of unusually long spans which need to besupported only at their ends. Thus, relatively few piers or foundationsupport points are required, thereby reducing construction costsgenerally and affording additional design capabilities, especially withunusual terrain and with difficult soil conditions.

As before, the inner base perimeter of the vertical walls of the room ischaracterized by a horizontal sealing strip covered by a wooden retainerstrip secured by fasteners located along the retainer strip atappropriate intervals. The bottom edges of the vertical wall units 115are supported on the retainer strip 140 and the sealing strip 135; andthe lower end of the adjacent inner skin 23 of the unit 115 extendsdownwardly to provide a skirt covering the exposed vertical edges of thestrips 135 and 140 (see FIG. 16). The outer skin 24 of the vertical wallunit is bent to provide a pair of flanges 157 secured to opposite sidesof the vertical beams 136 by fasteners 158. The two beams 136 and thetwo interposed webs 133 are themselves clamped together by suitablethrough bolt type fasteners 159. As before, a pair of vertical sealingstrips 141 is interposed between each of the vertical side edges of thecore and the adjacent vertical surfaces of the vertical beams 136.Appropriate fasteners are used, such as staples 144, which are powerdriven into the inner, flush panel surfaces 23 and the underlyingconnector members.

As appears most clearly in FIGS. 15 and 16, the floor joists 126 andattendant floor units 116 can be extended beyond the right-hand one ofthe girders 119 so as to provide the cantilevered deck 114, a rail 160being added to the outer end of the deck as is customary. In comparablefashion, the roof units 114 and attendant connectors can be extendedwell beyond the supporting upper end of the right-hand wall units 115 soas to afi'ord an overhang 113 suitably sealed and closed by fascia board165.

As particularly appears in FIG. 15 and in FIG. 18 (which is afragmentary sectional view taken on the vertical central plane betweentwo adjoining units 114 and two left-hand wall units 115) the uppermostedges 161 of the two central vertical metal webs 133 of the verticalwall connectors are cut at an angle equal to the slope of the roof units114 and are located so as to abut the corresponding sloping lower edge162 of the central metal webs 133 of the superposed roof panel connector166. The two abutting web plates 133 are welded along the joint betweenthe edges 161 and 162 and thereby afford a very strong haunch, or wallto roof, construction. A comparable welded construction is utilized inthe gable roof of FIGS. 1, 3 and 4.

Where the gauge of the web material is quite light, the metal webs canbe overlapped and secured together as by spot welding rather than bybutt welding, as above.

A welded joint construction similar to that described above for the wallto roof junction can advantageously be utilized, if desired, between thehorizontal floor connector metal webs and the metal webs of the verticalwall unit connectors.

As appears most clearly in FIG. 19, the structural units themselves(i.e., without connecting members) afford structural integrity of a highorder. FIG. 19 is a graph indicating, as an abscissa, the distance infeet, in decreasing order, which a4 ft. X ft. unit (of the typeheretofore disclosed) can span without deflecting more than theconventional permissible deflection ratio of 180 to 1. The ordinate isthe extent of the uniform load in pounds per square feet upon a unit.

The bottom curve, designated by the reference numeral 1000, illustratesthe relationship between span and load for a plain unit, i.e., a unit 4ft. X 20 ft. X 4 inches, as previously'described, without any connectingmeans joining two units together.

It will be noted from curve 1000 that if a plain 4 ft. X 20 ft. X 4inches unit of this type is placed in a horizontal attitude and issupported at its extreme ends, a uniform load of approximately 17.5pounds per square foot can be loaded on the entire upper surface of the4 ft. X 20 ft. X 4 inches unit before the deflection exceeds the 180 to1 limit. If supports are placed only ten feet apart, the permissibleload amounts to 65 pounds per square feet, and at a span of five feetthe permissible uniform load mounts to 130 pounds per square 'feet.

The other curves illustrate the substantial increases in span madepossible by different kinds of connectors.

, thickness aluminum skins.

For a 4 inches X 20 inches X 4 ft. plain unit, the permissible uniformload for an 18 foot span without exceeding the 180 to 1 limit is abouttwenty one pounds per square feet. 1

When two of the 4 n. x 20 ft. x 4 inches are joined together along theirtwo elongated, adjacent, lateral edges with a connector 71 of theflush-flush type 11- lustrated in FIG. 9, the uniform permissible loadincreases from 21 to approximately 31 pounds per square foot for a spanof eighteen feet, as can be seen by referring to the curve 900. Thecross-section of the beams in this case is 4 inches by 4 inches plywood;one of the plates 72 is 14 gauge galvanized iron, 4 inches wide; theother plate 72 is 26 gauge by 4 inches wide.

The project one-side type with the connector means 95 shown in FIG. 13)appears on the chart as curve 1300. For a span of 18 feet, the connectedstructural units do not reachthe 180 to 1 deflection point until auniform load of 35 pounds per square foot is imposed. The two web plates97 in this instance are each 20 gauge galvanized iron, 5 inches inwidth.

Curve 1400 illustrates the span versus uniform load characteristics ofstructural units joined by connectors of the project one-side typeillustrated in FIG. 14 wherein each of the two beams 36 is 4 /s inches X6 inches plywood with-the'two web-plates 33, each 16 gauge by 6 incheswide galvanized iron. The uniform load bearing capacity for a span of 18feet is 42 pounds per square foot.

Curve 1200 relates to a project-project type of connecting means,comparable to means 92 in FIG. 12, in which there are no wooden fillermembers, or additives, but only metallic web plates. In the exampleshown in cruve 1200 there are two 20 gauge by 6 inches galvanized ironplates and two 16 gauge by 8 inches galvanized iron plates. For a spanof eighteen feet the uniform load value is 71 pounds per square foot.

Curve 200 shows the coordinates resulting from the use of a projectonesside connector 31 as shown in FIG. 2, with each beam 4 )4; inches X8 inches in size and each web of 16 gauge galvanized iron, 8 inches inwidth. For a span of eighteen feet, the permissible uniform loadingincreases substantially, to a value of 79 pounds per square foot.

' It is interesting to note that the same coordinates of 18 feet spanand 79 pounds per square foot loading also obtain for theproject-project or project bothsides type of connector 61 as illustratedin FIG. 8. The curve 800 shows the'characteristics where the beams 63are each 4 54; inches X 8 inches in cross-section and the web plates 62are 8 inches in width and are of 16 gauge thickness of galvanized iron.The curves 200 and 800, in other words, are substantially identical.

The building structural system of the present invention is especiallycharacterized by its flexibility and adaptability to meet substantiallyall design requirement. In some instances, for example, the connectingmembers comprise only wooden beams, with no metal plates. Curve 2000,for example, shows the load values for 4 inches panels with two 2 inchesX 12 inches Douglas Fir webs. For 18 feet, the load is a very high 178pounds per square foot.

By varying the number, size and kind of units'and connectors, extensivefamilies of curves are worked out. ,Then, with predetermined designrequirements of loading, span, connector shape, size and the customaryadditional parameters, the most suitable configurations can readily bedetermined for any type of structure. Cost data and curves are alsocomputed and made available for reference in connection with each designdecision.

What is claimed is:

l. A building structural system comprising:

a. a plurality of laminated structural units, each unit including a pairof metal skins, each skin having an outer surface and an inner surface,and a core of material having low thermal conductivity bonded to saidinner surfaces of said skins, said laminated units being rectangular andextending longitudinally between opposite ends and transversely betweenopposite sides, said ends and said sides being defined by marginaledges; and

b. connector means for joining said units along adjacent marginal edges,said unit connector means including a pad comprising a sealing strip ofresilient material mounted on each of the adjacent edges of said units,and a metal web located on the exposed face of each .of said resilientsealing strips, said metal webs being arranged in abutting relation andfastened together.

2. A building structural system as in claim 1 further including a beaminterposed between each of said pads and said metal webs, said beamhaving a thickness such as to provide additional dimensional precisionand structural strength to the joint formed by the adjacent marginaledges of said units, and by said webs and said pads when tightlyconnected together with adjacent surfaces in face to face engagement.

3. A building structural system as in claim 1 wherein one edge of eachof said metal webs is substantially flush with the plane of one sidesurface of adjacent pairs of units, and the other edge of each of saidmetal webs extends beyond the plane of the other side surface of saidadjacent pairs of units to form a projection.

4. A building structural system as in claim 1 wherein both edges of saidmetal webs extend beyond the corresponding planes of said side surfacesof said units to form a pair of oppositely extending projections.

5. A building structural system as in claim 1 wherein both edges of saidmetal webs are flush with the planes of said side surfaces of saidunits.

6. A building structural system as in claim 2 wherein both edges of saidwebs and said beams are flush with the corresponding planes of said sidesurfaces of said units.

7. A building structural system as in claim 2 wherein one edge of saidwebs and said beams are substantially flush with the correspondingplanes of one of said side surfaces of said units and the opposite edgeof said webs and said beams project from the planes of the other of saidside surfaces of said units.

8. A building structural system as in claim 2 wherein both edges of saidwebs and said beams project from the corresponding planes of said sidesurfaces of said units.

9. A building structural system as in claim lincluding elongatedprotective cap means for covering said connector means.

10. A building structural system as in claim 9 wherein said protectivecap means comprise an elongated strip of material having an invertedU-shape in transverse section, and means for securing said cap means tothe adjacent portions of a pair of abutting units connected by saidconnector means.

11. A building structural system comprising:

a. a plurality of laminated structural units, each unit including:

1. a pair of skins each having an outer surface and an inner surface;and,

2. a core of material having low thermal conductivity interposed betweensaid pair of skins and bonded to said inner surfaces thereof; saidlaminated units being defined by marginal edges; and,

b. connector means for joining said units along adjacent marginal edges,said connector means includmg:

1. a pad comprising a sealing strip of resilient material mounted oneach of the adjacent edges of said units; and,

2. a web located on the exposed face of each of said sealing strips,said webs being arranged in abutting relation and fastened together.

12. A building structural system as in claim 11 further including a beaminterposed between each of said pads and said webs, said beam having athickness such as to. provide additional dimensional precision andstructural strength to the joint formed by the adjacent marginal edgesof said units and by said webs and said pads when tightly connectedtogether with adjacent surfaces in face to face engagement;

1. A building structural system comprising: a. a plurality of laminatedstructural units, each unit including a pair of metal skins, each skinhaving an outer surface and an inner surface, and a core of materialhaving low thermal conductivity bonded to said inner surfaces of saidskins, said laminated units being rectangular and extendinglongitudinally between opposite ends and transversely between oppositesides, said ends and said sides being defined by marginal edges; and b.connector means for joining said units along adjacent marginal edges,said unit connector means including a pad comprising a sealing strip ofresilient material mounted on each of the adjacent edges of said units,and a metal web located on the exposed face Of each of said resilientsealing strips, said metal webs being arranged in abutting relation andfastened together.
 2. a web located on the exposed face of each of saidsealing strips, said webs being arranged in abutting relation andfastened together.
 2. A building structural system as in claim 1 furtherincluding a beam interposed between each of said pads and said metalwebs, said beam having a thickness such as to provide additionaldimensional precision and structural strength to the joint formed by theadjacent marginal edges of said units, and by said webs and said padswhen tightly connected together with adjacent surfaces in face to faceengagement.
 2. a core of material having low thermal conductivityinterposed between said pair of skins and bonded to said inner surfacesthereof; said laminated units being defined by marginal edges; and, b.connector means for joining said units along adjacent marginal edges,said connector means including:
 3. A building structural system as inclaim 1 wherein one edge of each of said metal webs is substantiallyflush with the plane of one side surface of adjacent pairs of units, andthe other edge of each of said metal webs extends beyond the plane ofthe other side surface of said adjacent pairs of units to form aprojection.
 4. A building structural system as in claim 1 wherein bothedges of said metal webs extend beyond the corresponding planes of saidside surfaces of said units to form a pair of oppositely extendingprojections.
 5. A building structural system as in claim 1 wherein bothedges of said metal webs are flush with the planes of said side surfacesof said units.
 6. A building structural system as in claim 2 whereinboth edges of said webs and said beams are flush with the correspondingplanes of said side surfaces of said units.
 7. A building structuralsystem as in claim 2 wherein one edge of said webs and said beams aresubstantially flush with the corresponding planes of one of said sidesurfaces of said units and the opposite edge of said webs and said beamsproject from the planes of the other of said side surfaces of saidunits.
 8. A building structural system as in claim 2 wherein both edgesof said webs and said beams project from the corresponding planes ofsaid side surfaces of said units.
 9. A building structural system as inclaim 1 including elongated protective cap means for covering saidconnector means.
 10. A building structural system as in claim 9 whereinsaid protective cap means comprise an elongated strip of material havingan inverted U-shape in transverse section, and means for securing saidcap means to the adjacent portions of a pair of abutting units connectedby said connector means.
 11. A building structural system comprising: a.a plurality of laminated structural units, each unit including:
 12. Abuilding structural system as in claim 11 further including a beaminterposed between each of said pads and said webs, said beam having athickness such as to provide additional dimensional precision andstructural strength to the joint formed by the adjacent marginal edgesof said units and by said webs and said pads when tightly connectedtogether with adjacent surfaces in face to face engagement.